CHAP. r.J THE BALANCE OF NATUKE. 33 



dently fixed upon a good food-giving centre, was too infantile 

 to be able to stand the heavy draughts that were all at once 

 made upon it. Schools or shoals of fish, when they are of 

 such an extent as will admit of constant fishing, must have 

 been forming during long periods of time ; for we know that, 

 despite the wonderful fecundity of all kinds of sea fish, the 

 expenditure of both seed and life is something tremendous. 

 We may rest assured that, if a female cod-fish yields its roe 

 by millions, a balancing-power exists in the water that pre- 

 vents the bulk of them from coming to life,' or at any rate 

 from reaching maturity. If it were not so, how came it, in 

 the days when there was no fish commerce, and when man 

 only killed the denizens of the sea for the supply of his in- 

 dividual wants, that our waters were not, so to speak, im- 

 passable from a superfluity of fish? Buffon has said that 

 if a pair of herrings were left to breed and multiply undis- 

 turbed for a period of twenty years, they would yield a fish 

 bulk equal to the whole of the globe in which we live ! 



The subject of fish growth particularly as regards the 

 changes undergone by the salmon family will be found 

 further elucidated under the head of " Fish Culture," and in- 

 cidentally in some other divisions of this work. 



